Brown Noddy
Anous
stolidus stolidus

At a glance

Pantropical
distribution.
Largest of the noddy terns
Second most common seabird in the West Indies, but region’s population
in decline
Nest location, nest construction, and on-set of nesting season varies
from site to site
Better information on number of breeding colonies and number nesting
pairs needed

Index

Identification:

There
are only
three species of all black terns in our region. The Black Tern is
smaller than the two Atlantic species of noddy terns, and they have
white underwings. Non-breeding Black Terns are not entirely black. Of
the two noddy terns the Brown Noddy is larger (16-18 inches; 40-45 cm,
total length) than the Black Noddy (14-15 inches; 35-39 cm total
length). Both noddy terns have white caps. As it's name implies this
species is brownish and less dark. It also has a larger broader bill.
That said, these terns would be very difficult to identify in flight at
sea or when both species are not available for direct comparison.

Adults

Can
live up to
25 years, first breeds at 3-7 years of age. Sexes alike in appearance
but males larger than females, no seasonal variation in plumage. Dull
brown with conspicuous white cap. Primaries and tail darker than rest
of body giving birds in flight a two toned appearance. Black Noddy
dorsal color basically uniform.

Juveniles

Like
adult but
head and forehead all dark, whitish tips to secondaries and secondary
wing coverts. Immature looks like adult but does not have well defined
cap.

Alternative
names

French:
Noddi niais

Spanish:
Charran bobo, Charran pardelo, Cevera.

Systematics

Noddies
are
primitive terns, perhaps more closely related to gulls than they are to
other terns. Worldwide four species of noddies; only two the Brown and
Black occur in the Atlantic and West Indies region. The Brown Noddy is
the most abundant and wide ranging of the four species. Four recognized
subspecies, A. s.
stolidus is the only one occurring in the Atlantic.
This race is small, paler and has a whiter forehead than the other
subspecies.

Likely locations

Near
nesting
islands, does not venture far from land when nesting but will feed
offshore. Displaced after hurricanes into waters off southeastern
United States.

Distribution

This is a
common
tropical pelagic tern occurring in the Pacific, Atlantic, and Indian
Ocean; it is the second most abundant tropical seabird in the Atlantic.
Except following hurricanes and other major storms, the Brown Noddy is
seldom encountered away from tropical and sub-tropical seas.

Breeds
throughout the Caribbean Basin, lower Gulf of Mexico and Bahamas.
Absent from Bermuda. Move south of nesting colonies in winter. Same
subspecies also nests in equatorial and tropical south Atlantic
(Ascension Island, St. Helena, Tristan de Cunha and Gough Island).

Biology

At
sea

Tropical
seas.
Flies above and swims on surface. Roost on water, rocks. pilings and
flotsam. Feeds over coastal and offshore waters but not as pelagic as
Sooty Terns. Feeds by dipping or surface seizing. Often in mixed
species flocks over feeding schools of predatory fishes. Feeds
primarily on Spanish sardines and small larval fishes,
including
anchovies. Also know to eat squid. Prey items range from 30-100 mm in
total length.

At
the nest

Egg laying
dates
variable from colony to colony and can shift over time. Nest
construction also variable from simple scrape to loose twig nest in
vegetation. Often nest on cliffs. Single large white egg with sparse
brown blotches and specks. Incubation 33-36 days. Fledge in 43-49 days,
with parents continuing to feed young for at least the next hundred
days.

Islands of northern South American coast:
7,000-9,000 pairs (Van Halewyn and Norton 1984)

Total
for Western North Atlantic: 20,000-89,000 pairs depending on the Bahamas numbers

Kushlan,
et al. (2002) estimate the total population in the Americas as
286,000-298,000 adults (143,000-149,000 pairs). This discrepancy is
only in part explained by additional pairs nesting off the tropical
Pacific coast of Mexico and Central America.

Conservation Status

Because of
its
abundance in the western north Atlantic and other oceans this tern is
not a species of conservation concern. At Dry Tortugas, Florida,
species is listed as one of special conservation concern by the state
of Florida. Extirpated from several cays in Jamaica as a result of
egging and overall West Indian population is in decline. This decline
is a result of continuous loss of habitat and predation.

Conservation Needs

A
reassessment
of the region’s current population size is needed as many sites have
not been visited in decades. An accurate census of Bahaman populations
is particularly needed. These noddies nest on numerous small cays and
rocks and the aggregate population is likely to be many times larger
than what is currently reported. Many of these sites have difficult
access and surveys will probably need to be done from boats.

In
the West Indies adults have high survival rates (90% in studies
populations). On a global basis the species is well studied but only
two populations in the West Indies region have been investigated (Dry
Tortugas and Culebra). Because of the variation in the nesting biology
between different sites it would be beneficial to learn more about
other colonies, particularly some of the small isolated ones.

Only
four sites support 1,000 pairs or more and while two are protected, the
others deserve protection priority. Rats can quickly destroy the
nesting productivity of specific populations and monitoring for the
presence of Rattus should become routine protocol for researchers
visiting nesting colonies of noddies and other seabirds.
Rhesus
monkeys introduced to Desecheo Island (Puerto Rico) eliminated all
species of nesting seabirds from that island.

Nesting
sites need protection from egging and unintentional disturbance from
recreational boaters, and their dogs. Issuing licenses and quotas for
Sooty and Brown Noddy Tern eggs in Jamaica proved to be unenforceable.
We are aware of one nesting colony in the Bahamas where Australian
pines have taken over half of the island and the nesting noddies are
now restricted to the half with natural vegetation. These trees should
be removed from all islands and cays that have nesting seabird
colonies.

West
Indian Breeding Seabird Atlas by Will
Mackin and David Lee is licensed
under a Creative
Commons Attribution-Noncommercial-No Derivative Works 3.0 United States
License. Based on
work at www.wicbirds.net.
Permissions beyond the scope of this license may be available at www.wicbirds.net.